Presbyopia is an inevitable age-related impairment of near vision resulting from a decrease in the eye's accommodative ability. A number of approaches for treating presbyopia have been proposed, but they suffer from significant shortcomings and drawbacks. Human eyes that require vision correction often contain inherent levels of spherical aberration, typically positive. That is, the power of the human eye increases from the center of the pupil to the pupil margins. This spherical aberration can be defined as a power difference between the pupil center and pupil margins, or by some standard (e.g. Zernike or Seidel), or some non-standard radially varying power (symmetric or non-symmetric), wavefront slope or wavefront phase error. Other eyes that require correction contain inherent levels of negative spherical aberration. That is, the power of the human eye decreases from the center of the pupil to the pupil margins. This same situation may exist in eyes following cataract surgery (e.g. pseudophakic eyes). Conventional corrections may also include a modulation of power as a function of distance from the lens center. In some the lowest lens power is in the lens center, and highest in the periphery, and in others, the converse is true. This change in lens power from the lens center to the periphery can be discrete (e.g. bifocal, trifocal) or continuous (e.g. multifocal). In each case, the resultant power distribution or spherical aberration causing a simultaneous vision add effect attained by the wearer is determined by the resultant sum of the distribution of power across the pupil of both the eye plus the lens. Some approaches propose simultaneous vision or multifocal contact lenses that introduce spherical aberration to an eye-lens system to provide simultaneous near and distance correction. Such approaches suffer from a number of disadvantages. For example, decentration of lenses following this approach introduces coma, prism and other aberration. Some approaches propose correcting all the spherical aberration within a patient's eye, while others propose only partially correcting any spherical aberration existing in a patient's eye in order to leave residual spherical aberration after correction. The full-correction spherical aberration approaches are limited because they correct the spherical aberration required to provide multifocality, or after correcting spherical aberration require the introduction of larger amounts of spherical aberration. The partial spherical aberration correction approaches are limited and can only provide spherical aberration less than that existing in the uncorrected eye. At best such approaches provide a limited advantage over complete correction of existing spherical aberration. There remains significant disagreement as to corrective approaches with respect to spherical aberration. Some approaches argue complete correction is best, some argue partial correction is best, some argue for no correction of spherical aberration. Other approaches directed to presbyopia correction focus on adding spherical aberration without considering existing spherical aberration. Furthermore, confusion among these approaches has arisen because some presbyopic corrective lens designs have discrete add power zones within which they try to correct spherical aberration (completely or partially). Presbyopia continues to present significant unmet challenges and difficulties for vision correction both alone and in combination with correction of other conditions.